How much of a risk is space junk?

Space junk. It might sound like an out-of-this-world problem that we don’t need to worry about here on Earth – but is it? As we send more and more metal in the form of satellites up into space, scientists are warning it is becoming more of a risk both here – and up there. We dig into the problem and what’s being done to clean it up. Also this week, we answer a listener question about oceans and their influence on global temperatures, and we ponder the use – and sometimes abuse – of scientific language. And with the Paris Olympics well under way, how much does sex affect sporting performance? Presenter: Victoria Gill Producers: Ella Hubber & Gerry Holt Editor: Martin Smith Production Co-ordinator: Jana Bennett-Holesworth